SR Bad idle. DD please help

[Boltarsenal42]

The car is a 1990 s13 with (possibly) a Type X SR. Ok, heres what happened. I drove car to work, ran perfect. Drove car to shop to put on brakes, ran perfect, car gets off lift, idles terrible. It idles fine if the MAF is unplugged, so i thought it was something with the MAF. Bought a MAF, made sure wiring was secure and the same problem. it started fine at first and idled fine, but when i drove around the parking lot, it cut out on my and died. My starter was bad and i replaced it, and theres still nothing, and idles terrible. I need suggestions on how to fix it because this is my daily. ive also checked the IACV, and had no luck. im not sure where to go from here.

[AsleepAltima]

have you checked the simple things, like making sure the fuel filter is flowing well? getting 12 volts to your fuel pump and relay?

[jr_ss]

Did you check the MAF you replaced the bad one with? Replacing one bad MAF with another bad one will give you the same symptoms. What's your fuel pressure and timing set at? Check your MAF with an OHM meter? TPS check out ok?

[AsleepAltima]

all of those wouldnt cause it to just die though. the maf will, but not the settings on the others.

[jr_ss]

Getting an idea of the status of his motor. Zero fuel pressure will cause his car to just die... Weak fuel pump will cause that.

[AsleepAltima]

thats why i asked him about the basics. but even a weak pump will allow an idle. hes losing it completely. clogged filters or overloaded relays can commonly do that.

[AutechKouki]

Bad ecu.
Just spent a day last week diagnosing a similar issue on a buddy's car. Car idled fine with maf unplugged, as soon as plugged in car sputtered and died. Harness had continuity and at the most .02 resistance on my fluke. Maf was a tested working one. Replaced ecu and problem was/is no longer present.
It was weird because there was no reason the ecu should of failed, but it did.

I would find a pinout and check resistance on harness wires first. Check to make sure your ground are good too.

[AsleepAltima]

i love how people ask a question and then never check back in. why even bother to post?

[Boltarsenal42]

Internets been down for a few days. I went through all the recommendations, everything was fine. Turns out the blow off valve was stuck open, no idea how, but removed it and put a new one on and the problems fixed, thanks for the help everyone.

[AsleepAltima]

the blow off valve was causing it to die?

[AsleepAltima]

well, nevermind on that one. its a huge intake leak. i can see it.

[Boltarsenal42]

Yeah, I was messin around with it and my han passed over it and I felt the air coming from it. So I just covered it with my hand and the idle went normal, so I just switched it and no problems since then.